Having problems printing XT-CF

#1
Hi!

I'm having problems printing XT-CF on my gMax 1.5
Currently Im using the following settings:

Printer itself:

E3D Full metal hotend
0.4mm Nozzle (ruby Nozzle)

Layerhight 0.3mm
10% triangular infill
2 Outlines
3 bottom and top layers

30mm/s default speed
80% underspeed onoutline and solid infill

Temp nozzle 280/260 (have to print about 10 degrees hotter with the Ruby Nozzle)
Bed at 90 degrees

Whats happening is that when the first three layers are printed (prints perfect) and the two outlines are printed on layer 4 it starts skipping on the infill?

Even if I lower speed really low its skipping, and I cant understand why?
PLA seems to print just great! Is the PSU to weak to handle the high temps?

I know that I'm pushing it with the layer height, but I really need perfect layer adhesion, and the object is 500mm tall, so I would really manage to print at 0.3mm layer heights. I've also tested a 0.8mm nozzle at 0.3mm layers, 0.4 and 0.6 mm layers but I cant get rid of the skipping.

Attached the STL file if you want to take a look at it!

https://drive.google.com/open?id=0B21eO ... ndwQ2tDSU0

Im testing 0.2mm layers now, and I cant see any difference, it still skips at 30mm/s:

Swiched to NGEN printing at 250c (0.3mm layers), and that prints fine at 30mm/s and 130% speed (just occasional skipping during infill..)
 
#2
Conclusions from today, I can print NGEN faster, at an acceptable speed for 0.3mm layers with a 0.4mm nozzle.
Was thinking about my high temps, maybe that is causing some issues with clogging, so I lowered the temp to 260 for first layer and 250 for second layer, and the skipping came directly, even at 65% of the default 30mm/s speed, so thats really slow.

The same spool of XT-CF prints perfect on my Prusa i3 MK2 with 0.4mm nozzle and 0.3mm layers.

Second layer looks like this:



I tested to raise the nozzle through the BabystepZ and that helped (see the below picture) for the time beeing, but at the next layer the nozzle was WAY to high to put the outline down.

Could there be any issues with my Z height settings? I know for example that the Ruby Nozzle is like 1-2mm shorter than the Microswiss nozzle, but I've adjusted for that with my first layer height and babystep Z adjustment when the print starts.
 
#3
Switched model! Just for testing purposes!
Printing a Vase, 3 outlines, no infill, no bottom layer, no top layer, just a more constant flow.
Started at 250 degrees, had skipping at 60% of default (30mm/s) speed.
Raised the temp to 270 and Im printing at 100% now without skipping so far, also upped the speed to 120% and that seems to work! 150% gave me some skipping again. So 120% is 36mm/s, which must be acceptable for 0.3mm layers through a 0.4mm nozzle.
 
#4
Further testing made, this seems to be something else than issues with XT-CF in particular.
Im printing with PLA atm, at around 30-40mm speed, 0.24mm layer heights and I get skipping (on the infill) now aswell??

Sliced with S3D
 
#5
Further testing made and at the moment it seems like the XT-CF filament leaves alot of Debris in the nozzle, which might cause this clogging and skipping that I've experienced. Although Ive printed alot of XT-CF without cleaning the nozzle in between the prints without similar issues (same hotend as the gMax)

I'm currently printing PLA tests as 70-90mm/s with my 0.4mm nozzle, PLA and NO skipping!
Will continue the testing but it looks like I've found the source of my issue.